{"instruction": "You are an expert in named entity recognition. Please extract entities that match the schema definition from the input. Return an empty list if the entity type does not exist. Please respond in the format of a JSON string.", "schema": ["Chemical"], "input": "Separate groups of mice underwent 3 consecutive days of the same exposure sequence for 3h each consisting of the following : ( 1 ) 6h of filtered air ( FAFA ) , ( 2 ) O ( 3 ) then FA ( O ( 3 ) FA ) , ( 3 ) FA then carbon black ( FACB ) , or ( 4 ) O ( 3 ) then CB ."}
{"Chemical": ["O ( 3 )", "carbon black"]}